E2 Interference Effects in the C(α,γ0)16O12 Reaction
Abstract
The E1-E2 interference sign between the Ec.m.=2.68-MeV E2 resonance and an underlying E1 strength has been measured for the first time. An E1-E2 asymmetry parameter of a=0.07±0.05 was extracted from the thick-target γ-ray yields of the narrow resonance at angles of 45° and 135°. The positive sign of a corresponded to constructive interference at forward angles and, further, allowed the interference between the resonance and an E2 background to be identified as constructive below the resonance energy. The E2-E2 interference was then used to evaluate the global SE2 data within the vicinity of the resonance 2.5≤Ec.m.≤3.0MeV. An analysis of the global SE2 data that agreed with the interference scenario has determined the E2-E2 interference scheme of the 4.34-MeV resonance and background, resulting in a value of SE2(300)=62-6+9keVb.
- Publication:
-
Physical Review Letters
- Pub Date:
- October 2012
- DOI:
- 10.1103/PhysRevLett.109.142501
- Bibcode:
- 2012PhRvL.109n2501S
- Keywords:
-
- 26.20.-f;
- 25.55.-e;
- 23.20.En;
- 29.85.-c;
- Hydrostatic stellar nucleosynthesis;
- <sup>3</sup>H- <sup>3</sup>He- and <sup>4</sup>He-induced reactions;
- Angular distribution and correlation measurements;
- Computer data analysis